In the above cited patent application Ser. No. 357,714 as well as the article by Shmuel J. Merhav entitled "A Nongyroscopic Inertial Measurement Unit" published May 1981 by Technion Israel Institute of Technology, a method and apparatus for measuring the specific force vector and angular rate vector of a moving body by means of a plurality of cyclically driven accelerometers is disclosed. The co-pending patent application Ser. No. 357,715 cited above discloses similar techniques for measuring the specific force vector and angular rate vector of a moving body utilizing either a single or a pair of accelerometers vibrating at a constant frequency.
In the Merhav patent application Ser. No. 526,776 filed Sept. 2, 1983, one of the embodiments of the rate sensor utilizing two vibrating accelerometers is an arrangement whereby the accelerometers are orientated in a back-to-back arrangement, that is with their force sensing axes aligned in opposite directions, and wherein the accelerometers are vibrated in a substantially linear direction normal to the force sensing axes. One application of such a rate sensor would be in an inertial reference system that could be used in an aircraft inertial navigation system. In such an application, it is important to keep the mechanism for vibrating the accelerometers as simple as possible as well as to reduce the size and the cost of the system. It is also considered very desirable to eliminate insofar as possible the number of parts that can wear in such a system.